Exploring the Structural Relationship Between Interviewer and Self-Rated Affective Symptoms in Huntington's Disease.

This study explores the structural relationship between self-report and interview measures of affect in Huntington's disease. The findings suggest continued use of both to recognize the multidimensionality within a single common consideration of distress.

Huntington's Disease: Prevalence and Psychological Indicators of Pain.

BACKGROUND: Huntington's disease (HD) is a genetic neurodegenerative condition that involves impairments in movement, cognition, and mood. Research is lacking in HD with regard to the prevalence of pain and the relationships between psychological factors and pain. The aim of this research was to investigate the prevalence of pain and identify the psychological factors associated with pain severity in people with HD. METHODS: This data-mining study used data from 1474 people who participated in the European Huntington's Disease Network (EHDN) REGISTRY study. Pain severity was measured using the Medical Outcome Study 36-item short-form health survey. Separate ordinal regression analyses were conducted with participant-rated and interviewer-rated psychological measures (the Hospital Anxiety and Depression Scale-Snaith Irritability Scale and the Unified Huntington's Disease Rating Scale). The psychological factors considered were anxiety, depression, irritability, aggression, low self-esteem, and apathy. RESULTS: The prevalence of pain in the total sample was 41% (stage I, 42%; stage II, 44%; stage III, 39%; stages IV and V, 50%). After controlling for confounding variables, pain severity was significantly associated with participant-rated anxiety and depression. Interviewer-rated anxiety, depression, and irritability also were significantly associated with severity of pain after controlling for confounding variables. CONCLUSIONS: This research confirmed that pain is indeed an issue for people with HD, particularly during the later stages of the disease. Caregivers and health professionals should consider the possibility that people with HD might be experiencing pain, particularly if they are showing signs of anxiety, depression, or irritability.

Irritability in Huntington's Disease: Factor Analysis of Snaith's Irritability Scale.

BACKGROUND: Elevated levels of irritability are reported to occur in a number of neurological conditions, including Huntington's disease (HD), a genetic neurodegenerative disorder. Snaith's Irritability Scale (SIS) is used within HD research, but no psychometric evaluation of this instrument has previously been undertaken. Therefore, the current study aimed to analyze the factor structure of this scale among an HD population. METHODS: Exploratory and confirmatory factor analysis were used to examine the structural properties of SIS using responses from 1,264 HD gene expansion carriers, across 15 European countries, who were engaged in the REGISTRY 3 study. RESULTS: An exploratory factor analysis of a subsample of the data suggested a two-factor interpretation of the data comprising "temper" and "self-harm." Eight possible models were tested for goodness of fit using confirmatory factor analysis. Two bifactor models, testing general and group factors in the structure of the scale, provided an equivocal "good" fit to the data. The first comprised a general irritability factor and two group factors (as originally proposed using SIS): outward irritability and inward irritability. The second comprised a general irritability factor and two group factors (as proposed by the exploratory factor analysis): temper and self-harm. The findings from both models suggested that the loadings of items were higher on the general factor. CONCLUSIONS: Bifactor models are proposed to best consider the structure of the SIS, with findings suggesting that an overall score should be used to measure irritability within HD populations.